Process and apparatus for fire-polishing plate-glass.



PATENTED FEB. 5, 1907.

P. T. SIEVERT.

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS. APPLICATION FILED0012s, 1906.

7 SHEETSSHEET 1.

No. 843,238. PATENTBD FEB. 5, 1907, P. T. SIBVERT.

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS.

. APPLICATION FILED 00123. 1906.

7 SHEETS-SHEET 2.

rm: NORRIS PETERS co. WASHINGION. n, c.

No. 843,238. PATENTED FEB. 5, 1907. P. T. SIEVBRT.

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS. APPLICATION FILED00123, 1906.

7 SHBETS-SHEET 3.

m: NBRRIS PETERS cm, wnsnmcmu. a, c.

No. 843.238. PATENTED FEB. 5, 1907.

I P. TLSIBVBR'T. PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS.

"APPLICATION FILED 00T.23, 1906.

7' SHEETS-SHEET 4.

No. 843,238. PATENTED FEB. 5, 1907.

P. T. SIEVERT,

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS. APPLICATION FILED001 .23, 1906.

'7 SHEETS-SHEET w 59 CE 8 2 9 f 9g I 9mm WYMM a M 3 $0M aw PATENTED FEB.5, 1907.

T. SIBVERT.

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS.

APPLICATION FILED 0UT.23, 1906.

7 SHEETS-SHEET 6.

RS co, Asmumau, o. c.

No. 843,238. PATENTED FEB. 5, 1907.

P. T. SIEVBRT.

PROCESS AND APPARATUS FOR FIRE POLISHING PLATE GLASS.

- A APPLIOATION FILED 0012s, 1906.

7 SHEETS-SHEET 7.

PAUL THEODOR SIEVERT, OF DRESDEN, GERMANY.

PROCESS AND APPARATUS FOR FlRE POLlSHlNG. PLATE-GLASS.

Specification of Letters Patent.

Yatented Feb. 5, 1 907.

Application filed October 23, 1906. Serial 11c- 840,156.

To (LN whom/ 11/ 'III/(LJ/ concern:

Be it known that 1, PAUL Tnnooon SinvER'i, a subject of the Emperor ofGermany, residing at Dresden, in the Kingdom of Saxony, Germany, haveinvented a certain new and useful Improvement in a Process and Apparatusfor fire-Polishing Plate-Glass, of which the following is aspecification, accompanied by drawings.

Various suggestions have been made, among others by the applicanthimself, to fireolish plate-glass produced on iron surfaces by havingthem passed immediately on their completion in horizontal position orsuspended at one edge in front of meltingflames, by means of which theplate-glass is softened on the surface and can then take a lire-polish.These suggestions have not, however, given hitherto any practicallysatisfactory result. It is impossible to heat the whole surface of theglass plate by that method in good time in a permanent man ner and tosuch an extent as required for obtaining the success desired. On thecontrary, strains are produced which easily lead to the glass platebreaking.

According to this invention the process consists in suspending the plateby one edge in a vertical position and in several times introducing itinto and removing again from a fire-chamber capable of accemnnuiatingthe whole of the plate. In this way the whole of the surface of theplate is softened by renewed heating, and at the same time,

, owing to stretching under the influence of its own weight, it is madethinner and takes up fire-pa ish.

By introducing and again withdrawing therefrom a glass plate suspendedby means of one edge into a lire-chamber accommodat- 'ing the who eplate not only dangemus strains inside the glass are obviated, but it isalso possible, as already stated, to reduce as desired the thickness orto stretch in a straight line the softened glass plate by the action ofits own weight.

The polishing of the glass plate in the fire can be effected in suchmanner that it is introduced into the fire-chamber only in order to beleft ti .o until the polishing is completed. It is, however, betterpcatedly to introduce the glass plate into ire-chamber and to withdrawit again in order to allow it from time to time to solidify again,

to a certain extent, outside the fire-chamber and to prevent excessivelyquick softening and Ilmving of the glass mass.

.[f it is desired merely to polish glass plates, they can be introducedinto tle fire-chamber in any desired direction. It is, liO\\OYO1, bestto arrange it so that a glass plate should be moved vertically donnnard, and vice versa. T110 reduction of tie tiickness of glass plates bystrctcling in tire iire greatly assists the production of a very finepolish. In such cases it is advisable to roll tle glass plates a littlet) icker at the beginning and then stretch tlcm out subsequently to thedesired ti inncss, and ttis is facilitated by ieating tire iire-clnnnberin such manner that its teat increases u mard in a certain pro portion.Tic process is tien such that tie glass plates are introduced from thetop into tie open [ire chamber, and folloning tle stretc. ing of tlieplate taking place in ti o upper hot layer the said plate is gradually\vit ndrann through tle upper hotter layers of the fire-chamber and fromtie loner and cooler layers into tie open air. In tlie open air theglass plate solidifies fairly quickly and it is possible to give tleplate tlc de sired t1 ickncss by vitlLdrau ing it from tl1e lire-chambermore or less quickly. In such case it is useful to introduce ti 0 glassplate from time to time for a few seconds entirely into tielll'O-Cii2tll1l)Cl' in order to prevent trio portinis of t: c glassplate, ti o t, ickncss of which has been sulliciently reduced, and w,lOil have in ti o nieantiine solidified, from 'nking below a certaintemperature.

T. e introduction of glass plates in vertical direction into ti 0fire-clambcr, v\l ctl or only for ti o purpose of polis ing or forpolis: ing and reducing ti o t; ickncss, makes it ])tSSll1l6 to remove t0 glass plate from ti o rcllingtable and to introduce it into ti olire-clam,- bcr in a very quick and simple manncr. T. is is of great:nlvantagc, more particularly for t1 in rellul-glass plates, as goodresults can only be obtained by making t. e operations to follow eachoti er very quickly. For the purpose of reducing ti o t, ickncss ofglass plates tl'cir introduction into and rcmoval from ti o fire-chamberin vertical dircction is very advantageous, as ti 0 portion of tTc glassplate, ti 0 ti ickncss of \ii ich as already been reduced, can beremoved along l the whole of its idth from the fire-chamber ber.

into the open air for the purposes of solidification.

The apparatus for carrying out the process comprises, preferably, asuspension device arranged above a fire-chamber and enabling the glassplate to be vertically introduced into and removed from the fire-cham-The introduction and the \aitl'idrawal can be effected by means of ahoist of any desired well-known construction with adjustable speed.

The suspension device for the glass plate itself can have variousshapes. Thus, for instance, the glass plates could be simply seized, bymeans of tongs, and suspended to a support, or the edges of the glassplate could be flanged over and suspended direct on the support. A goodsuspension device must be, however, of such construction that itcompletely seizes the glass along one longitudinal edge, which is besteffected by clamping the edge between two flat iron bars.

Two constructions of the apparatus according to this invention areillustrated, by way of example, in the accompanying drawings and aresuitable for carrying out the process.

Figures 1 and 2 show an apparatus in which the glass plate is seized bythe support by means of a mechanical clamping device, and Figs. 37 adevice in which it is done by means of an electromagnet. Fig. 1 showsthe apparatus in side elevation in the position in which it is situatedafter tlie glass plate, which is still on the rollingtable, has beenseized. Fig. 2 shows the same apparatus after the introduction of tlteglass plate into the fire-chamber. Figs. 3 and 1 show the apparatus withelectromagnet in front and side elevation with the glass plate in thesame position as that shown in Fig. 1. Fig. 5 shows the apparatus afterthe raising of the glass plate. Fig. 6 shows the same apparatus afterthe removal of the rolling-table and immediately before the introductionof tie glass plate into the fire-chamber, and Fig. 7 shows the apparatusafter the introduction of the glass plate into the fire-cbamberj Theapparatus comprises first of all a support 1, which can be, forinstance, vertically adjustable in bearings 2. If desired, the supportcould of course be suspended in such manner as to enable it to be movedlaterally, turned, or swung in order to enable it to be brought into theposition required for seizing and transporting the glass plate.Generally, however, vertical adjustability of the support will besul'licient. The support is vertically moved by means of a motor 3forinstance, an electric motor. In the construction illustrated on thespindle of the electric motor is mounted a worm 4, engaging with aninclosed worm-wheel 5. On the spindle of the latter is mounted a toothedwheel 6,

. I the support.

It will be seen that by rotating he motor in one or in the otherdirection the support can be raised or lowered.

Vertically under the support is arranged a lire-chamber S, which can beheated in any desired mannerfor instance, by iiues 9. The -lire-chamberis generally closed by a cover 1 O, Vv'lliCil is suitably made in twoparts, which on being drawn apart uncover the inlet to the lire-chamber.

Laterally of the support and of the firechamber is arranged arolling-table 11, on wlich takes place the manufacture of glass platesin any desired and well-known manner. The rolling-table is preferablyarranged in such manner that it can be moved on its bottom frame 12laterally to such an extent that its front edge 13 comes over thefirechamber. The arrangement must be-such that after the rolling theglass plate is seized by the support 1, raised from the rolling-table11, and introduced into the fire-chamber 8. To that end must be provideda device enabling the support to be connected with the glass plate,preferably, as already stated, along the whole edge of the latter. Inthe construction shown in Fig. 1 this is effected by means of amechanical clamping device. Next to the front edge 13 of therolling-table 11 the latter is provided on the surface with a groove,into "l LlCl'l is placed a bar 14, made of any desired suitablematerialfor instance, iron. The said bar is arranged in such manner thatits upper edge is flush with the surface of the rolling-table At thebottom end of the support is provided a pin 15, on which are rotatablymounted two arms 16. These latter carry at their front ends a bar 17,which when the arms 16 are raised lies exactly over the bar 14, placedinto the rollingtable.

The working of the apparatus is as follows: After the rolling of theglass plate the rollingtable 11 is moved into the position shown inFig. 1. Then the support is lowered, and the arms 16, with the bar 17,folded in such manner that the said bar rests on thesurface of the glassplate exactly over the bar 1 1. Then the bars 14 and 17 are connectedtogetl:.er for instance, by means of screws 18and in this way the glassplate is clamped between the bars 14 and 17. Then the support 1 israised and takes with it the still flexible glass plate, so that"finally the latter after the turn ing of the arms 16 is suspended invertical position over the fire-drum. Tlien the roll ing-table is movedback, and when the firedrum is opened the glass plate can be introducedinto or withdrawn from the same, as desired.

The connection of the support with the glass plate can be effected in astill simpler manner by means of the clamping device described and of anelectromagnet, as shown engaging with a toothed rack 7 secured to 1 inFigs. 3 to 7. As regards the mounting of IIO the support, the fire-drum,and the rollingtable this apparatus is shown in Figs. 1 and 2; butinstead of tlie arms 16, with the clamping-bar 17, the bottom end of thesupport is provided with a fork 19, in which is suspended a frame 21,rotatable about a pin 20. The said frame is provided with. a series ofelectromagnets 22, as well as with balanceweights 23, which balance theweight of the electroniagnets.

In the groove at the front edge of the rolling-table is arranged a bar24, as shown in Figs. 1 and 2, made of some magnetic material-that is tosay, preferably cf iron. After the rolling-table on completion of therolling of the glass plate has been pushed under the support to such anextent that the bar comes to lie exactly under the poles of theelectromagnets 22 and the support lowered until the electromagnets comein contact with the surface of the glass plate and the saidelectromagnets excited they attract the iron bar 24, as armature, andthe glass plate is clamped between the electromagnet-pcles and the ironbar. When the support is raised, it carries with it the glass plate.This is shown in Fig. 5, in which it will be seen how the glass plate 25slightly bends when being raised from the rolling-table. As soon as itis freely suspended the rolling-table is moved back, (see Fig. 6,) andthen, as shown in Fig. 7, the glass plate can be lowered into thefire-drrnn.

The electromagnet must be of such construction as to withstand the highheat of the heating-drum. The insulation of the wind ing must thereforebe effected by means of some refractory materialfor instance, asbestosor the likein well-known manner.

The polished or the stretched and thinned glass plate is released fromthe support and in well-known manner finally cooled. in acooling-chamber or the like.

It is obvious that the kind of manufacture of the glass plate isimmaterial from the pc int of view of this invention. The latter can beapplied to glass plates manufactured in any desired HIZtIHlQI fQI'instant e, by rolling, casting, shaking, &c.

hat I. claim as my invention, and desire to secure by Letters Patent, is

1. The lverein-describei'l process for firepolishing plate-glass whichconsists in suspending a glass plate along one edge and introducing saidplate into and removing it from a heating-chamber capable ofaccommodating the whole plate.

2. The herein-described process for firepolislt-ing plate-glass whichconsists in suspending a glass plate along one edge and repeatedlyintroducing said plate into and removing it frrm a heating-chambercapable of acctmmodating the whole plate.

3. The herein-described process for firepolishing plate-glass whichconsists in suspending a glass plate along one edge in a vertiealdirection and introducing said plate into and removing it from aheating-chamber capable of accommodating the whole plate.

4. The herein-described process for firepolishing plate-glass whichconsists in suspending a glass plate along one edge in a verticaldirection, introducing said plate into and removing it from aheating-chamber capable of :weommodating the whole plate and repeatingthe introduction until the glass plate becomes stretched under theinfluence of its own weight.

The hereiii-described process for firepolishing plate-glass whichconsists in suspending a glass plate along one edge in a verticaldirection, introducing said plate into a heating-chamber capable ofaccommodating the whole plate, heating said chamber to a temperaturewhich increases upwardly. and conveying the glass plate from the cold orlower part of said chamber through the upper better part.

6. The herein-described process for firepolishing plate-glass whichconsists in suspending a glass plate along one edge in a verticaldirection, introducing said plate into a heating-clnimber capable ofaccommodating the whole plate, heating said chamber to a temperaturewhich increases upwardly, and conveying the glass plate from the cold orlower part of said chamber through the upper hotter part and regulatingthe rate at which the dill'erent portions of the glass plate areconveyed through said hot part.

7. In an apparatus for lirepolishing glass, the combination of a glassplate to be treated, a heating-chamber capable of accommodating thewhole plate, means for supporting said plate along one edge, and meansfor introducing said plate into and removing it from said heating-chamber.

S. In an apparatus for lire-polishing glass, the combination of a glassplate to be treated, a heatiug-chamber capable of aeconnnodating thewhole plate, means for supporting said. plate along one edge in avertical position, and means for introducing said plate into andremoving it from the heating-charm ber.

9. In an apparatus for 'lirepolishing glass, the combination of a glassplate to be treat ed, a heating-chamber capable of accommodating thewhole plate, means for supporting said plate along one edge in avertical position, means for intrmlucing said plate into and removing itfrom the heating-chamber, and means for stretching the glass plate underthe inlluence of its own weight.

10. In an apparatus for lire-polishing glass, the combination (if aglass plate to be treatd, a heatiug-clamber capable of accomm dating thewhole plate, means for i supporting said plate along one edge in a lvertical position, means for introducing said IIO &

plate into and removing it from the heatingchamber, means for stretchingthe glass plate under the influence of its own Weight, and means forheating said chamberto a temperature which increases upwardly.

11. In an apparatus for fire-polishing a glass plate, the combination ofa heatingchamber capable of accommodating the whole plate, a supportabove said chamber, means for raising and lowering said support, meansfor forming a body of glass into a plate, means for conveying the edgeof the glass plate over the chamber, a clamping device connected to thesupport, means for applying the clamping device to the edge of the platewhile said edge is over the heating-chamber, and means for removing saidconveying meanswhen the glass plate is lifted.

12. I11 an apparatus for fire-polishing a glass plate, the combinationof a heatingchamber capable of accommodating the whole plate, means forheating the chamber to a temperature which increases upwardly, a supportabove said chamber, means for raising and lowering said support, meansfor forming a body of glass into a plate, means for conveying the edgeof the plate over the chamber, a clamping device connected with thesupport, means for applying the clamping device to the edge of the platewhile said edge is over the chamber, means for removing said conveyingmeans when the lass is lifted and means for conveying the glass platefrom the cooler lower part through the upper hotter part of the chamberat a variable speed.

13. In an apparatus for fire-polishing glass, the combination of a glassplate to be treated, a fire-chamber capable of accommodating the wholeplate, a vertical movable support above said chamber, a clampingrleviceconnected to the support and arranged to grip the glass plate along oneedge, a motor operatively connected to said support to raise and lowerit and to introduce said plate into and remove it from the firecham 14.In an apparatus for fire-polishing glass, the combination of a glassplate to be treated, a fire-chamber capable of accommodating the wholeplate, a vertical movable support above said chamber, a clamping deviceconnected to the support and arranged to grip the glass plate along oneedge, a motor operatively connected to said support to raise and lowerit and to introduce said plate into and remove it from the fire-chamberin a vertical position.

15. In an apparatus for fire -polishing glass, the combination of aglass plate to be treated, a fire-chamber capable of accommodating thewhole plate, a vertical movable support above said chamber, a motoropereratively connected to said support to raise and lower it, aplate-rolling table mounted laterally of said chamber and support andhaving a groove on the top near one edge, means for bringing said edgeof the table over the chamber, a metal bar disposed in said groove withits upper face flush with the table-surface, a member connected with thesupport and arranged to register with said bar, means for pressing saidbar and member together to clamp the glass plate along one edge, andmeans for removing the rolling-table when the glass plate is lifted.

16. In an apparatus for fire polishing glass, the combination of a glassplate to be treated, a fire-chamber capable of accommodating the wholeplate, fiues in the walls of said chamber, means for heating saidchamber to a temperature which increases upwardly, a vertical movablesupport above said chamber, a motor operatively connected to saidsupport to raise and lower it, a platerolling table mounted laterally ofsaid chamber and support, means for bringing the edge of said table overthe chamber, a clamping device connected to the support and arranged togrip the glass plate along said edge, means for removing therolling-table when the glass plate is lifted, and means for conveyingthe glass plate from the cooler lower part through the upper hotter partof the chamber at a variable speed.

17. In an apparatus for fire-polishing glass, the combination of a glassplate to be treated, a fire-chamber capable of accommodating the wholeplate, a vertical movable support above said chamber, a motor operatively connected to said support to raise and lower it, a plate-rollingtable mounted laterally of said chamber and support and having a grooveon the top near one edge, means for bringing said edge of the table overthe chamber, an iron bar disposed in said groove with its upper faceflush with the tablesur face, a series of electromagnets secured to thesupport having poles arranged to register withthe iron bar, means forenergizing said electromagnets to attract said iron bar and clamp theglass plate along one edge and means for removing the rolling-table whenthe glass plate is lifted.

18. In an apparatus for fire polishing glass, the combination of a glassplate to be treated, a firechainber capable of accommodating the wholeplate, a vertical movable support above said chamber, a motoroperatively connected to said support to raise and lower it, aplate-rolling table mounted laterally of said chamber and support andhaving a groove on the top near one edge, means for bringing said edgeof the table over the chamber, an iron bar disposed in said groove withits upper face flush with the table-surface, a fork fixed to the bottomof the support, a rotatable frame mounted in said fork, a series ofelectromagnets carried in said frame having poles arranged to registerwith the iron bar, weights on said frame to balance the electromagnets,means for energizing said electromagnets to attract said iron bar andclamp the glass plate along one edge, and means for removing therolling-table when the glass plate is lifted.

19. In an apparatus for fire-polishing glass, the combination of a glassplate to be treated, a fire-chamber capable of accommodating the wholeplate, a vertical movable support ahove said chamber, a motoroperatively connected to said support to raise and lower it, aplate-rolling table mounted laterally of said chamber and support andhaving a groove on the top near one edge, means for bringing said edgeof the tacle over the chamber, an iron ioar disposed in said groove withits upper face flush with the table-surface, a series of electromagnetssecured to the support having poles arranged to register with the ironbar, means for energizing said electromagnets to attract said iron barand clamp the glass plate along one edge, means for removing therolling-table When the glass plate is lifted, means for heating thefirechamher to a temperature which increases upwardly and means forconveying the glass plate from the cooler lower part through the upperhotter part of the chamber at a variable speed.

20. The herein-described process for the polishing plate-glass, whichconsists in vertically suspending a plate-glass by one edge andintroducing said plate into and removing it from a heating-chamher.

21. The herein-described process for firepolishing plate-glass, whichconsists in vertically suspending a plate-glass by one edge andintroducing said plate into and removing it from a heating-chambercapable of accommodating the whole plate.

In witness whereof I have hereunto signed my name, this 3d day ofOctober, 1906, in the presence of two subscribing witnesses.

PAUL THEODOR SIEVERT.

W'itnesses:

PAUL AREAS, EMIL 0121).

